WO2008038419A1

WO2008038419A1 - Image display device and method, and image processing device and method

Info

Publication number: WO2008038419A1
Application number: PCT/JP2007/051914
Authority: WO
Inventors: Kenichiroh Yamamoto; Hiroyuki Furukawa; Masafumi Ueno; Yasuhiro Yoshida
Original assignee: Sharp Kabushiki Kaisha
Priority date: 2006-09-28
Filing date: 2007-02-05
Publication date: 2008-04-03
Also published as: JP4157579B2; EP2077663A4; US20100085478A1; JP2008107753A; EP2077663A1

Abstract

In an image display device provided with a frame rate conversion (FRC) unit, deterioration in the image quality of a telop portion is particularly prevented. An FRC unit (100) includes a moving vector detecting unit (101) and an interpolation frame generating unit (102). The moving vector detecting unit (101) is comprised of a frame delaying unit (1) for delaying an input signal by one frame, an initial displacement vector selecting unit (2) for selecting and outputting an initial displacement vector used for detecting a vector, a moving vector arithmetic operation unit (3) for detecting the moving vector by means of the initial displacement vector, a vector memory (4) for saving a vector detecting result, and a telop information detecting unit (5)for detecting more than one telop existing domains and their moving speed by using the vector detecting result for a previous frame supplied from the vector memory (4). The detecting result of the telop information detecting unit (5) is reflected in the processing of the initial vector displacement vector selecting unit (2) and/or the moving vector arithmetic operation unit (3), so that the accuracy for detecting a vector in the telop portion is improved.

Description

Specification

Image display apparatus and method, image processing apparatus and method

Technical field

TECHNICAL FIELD [0001] The present invention relates to an image display apparatus and method, an image processing apparatus and method having a function of converting a frame rate or a field rate, and in particular, an image display apparatus for preventing image quality deterioration of a telop portion and an image by the apparatus. The present invention relates to a display method, an image processing apparatus, and an image processing method using the apparatus.

Background art

[0002] In contrast to cathode ray tubes (CRTs), which have traditionally been used mainly for applications that embody moving images, LCDs (Liquid Crystal Displays) can be viewed when moving images are displayed. There is a drawback of so-called motion blur that the contour of the motion part is blurred and perceived by the person. It has been pointed out that this motion blur is caused by the LCD display method itself (for example, Patent No. 3295437; “Shuichi Ishiguro, Yasuro Kurita,” “8x CRT hold light-emitting display video) "Study on quality", IEICE Technical Report, IEICE, EID96-4 (1996-06), p. 19-26 ").

[0003] In a CRT that performs display by scanning an electron beam to emit light from a phosphor, the light emission of each pixel is almost impulse-like, although there is some afterglow of the phosphor. This is called an impulse-type display method. On the other hand, in an LCD, the charge stored by applying an electric field to the liquid crystal is held at a relatively high rate until the next electric field is applied. In particular, in the case of the TFT method, a TFT switch is provided for each dot constituting a pixel, and an auxiliary capacitor is usually provided for each pixel, so that the stored charge retention capability is extremely high. For this reason, light emission continues until the pixel is rewritten by applying an electric field based on image information of the next frame or field (hereinafter referred to as a frame). This is called the hold type display method.

[0004] In the hold-type display method as described above, the impulse response of the image display light has a time spread, so that the time-frequency characteristic deteriorates and the spatial frequency characteristic also decreases accordingly, resulting in motion blur. Occurs. In other words, a person's line of sight is smoothly added to moving objects. Therefore, if the light emission time is long as in the hold type, the motion of the image becomes jerky due to the time integration effect, and it looks unnatural.

[0005] In order to improve motion blur in the hold-type display method, a technique for converting a frame rate (the number of frames) by interpolating an image between frames is known. This technology is called FRC (Frame Rate Converter) and has been put into practical use in liquid crystal display devices.

[0006] Conventionally, as a method for converting the frame rate, there are various methods such as simply repeatedly reading the same frame multiple times and frame interpolation by linear interpolation between frames (for example, Tatsuro Yamauchi, “Television Conversion”, Journal of the Television Society, Vol. 45, No. 12, pp. 1534–1543 (1991)). However, in the case of frame interpolation processing by linear interpolation, motion unnaturalness (jerkiness, judder) due to frame rate conversion occurs, and the motion blur interference due to the hold type display method described above is sufficiently improved. The image quality was insufficient.

[0007] In order to eliminate the influence of the jerkiness and improve the moving image quality, motion compensation processing using a motion beta has been proposed. According to this motion compensation process, since the motion image is captured and compensated for motion, it is possible to obtain a very natural moving image with no deterioration in resolution and without occurrence of jerkiness. Furthermore, since the interpolated image signal is formed by motion compensation, it is possible to sufficiently improve the motion blur obstruction caused by the hold type display method described above.

[0008] In the above-mentioned Japanese Patent No. 3295437, an interpolated frame is generated adaptively by motion, thereby increasing the frame frequency of the display image and improving the reduction in spatial frequency characteristics that cause motion blur. Techniques for disclosing are disclosed. This is because at least one interpolated image signal to be interpolated between frames of the display image is formed adaptively to the front and rear frame force motion, and the formed interpolated image signal is interpolated between the frames and sequentially displayed. ing.

FIG. 1 is a block diagram showing a schematic configuration of an FRC drive display circuit in a conventional liquid crystal display device. In the figure, the FRC drive display circuit performs a motion compensation process between frames of an input image signal. An FRC unit 100 that converts the number of frames of an input image signal by interpolating the image signal, a liquid crystal layer, and electrodes for applying a scanning signal and a data signal to the liquid crystal layer. An active matrix liquid crystal display panel 104, and an electrode driving unit 103 for driving the scanning electrodes and data electrodes of the liquid crystal display panel 104 based on the image signal subjected to frame rate conversion by the FRC unit 100. It is prepared for.

[0010] The FRC unit 100 includes a motion vector detection unit 101 that detects motion vector information as well as an input image signal force, and an interpolation frame based on the motion vector information obtained by the motion vector detection unit 101! And an interpolation frame generation unit 102 for generation.

[0011] In the above configuration, the motion vector detecting unit 101 may obtain motion vector information using, for example, a block matching method or a gradient method, which will be described later, and in some form on the input image signal. If motion vector information is included, this may be used. For example, image data compression-encoded using the MP EG method includes motion vector information of a moving image calculated at the time of encoding, and this motion vector information may be obtained.

FIG. 2 is a diagram for explaining frame rate conversion processing by the conventional FRC drive display circuit shown in FIG. The FRC unit 100 generates an interpolated frame (image colored in gray in the figure) by motion compensation using the motion vector information output from the motion vector detection unit 101, and generates the generated frame. By sequentially outputting the interpolated frame signal together with the input frame signal, the frame rate of the input image signal is converted, for example, from 60 frames per second (60 Hz) to 120 frames per second (120 Hz).

FIG. 3 is a diagram for explaining interpolation frame generation processing by the motion vector detection unit 101 and the interpolation frame generation unit 102. The motion vector detection unit 101 detects the motion vector 105 from the frame # 1 and the frame # 2 shown in FIG. That is, the motion vector detection unit 101 obtains the motion vector 105 by measuring how much and in which direction the frame # 1 and frame # 2 have moved in 1/60 second. Next, interpolation frame generation section 102 allocates interpolation vector 106 between frame # 1 and frame # 2 using the obtained motion vector 105. An interpolation frame 107 is generated by moving the object (in this case, a car) from the position of frame # 1 to the position 1Z120 seconds later based on this interpolation vector 106.

[0014] In this way, motion compensation frame interpolation processing is performed using motion vector information, and display frames are displayed. By increasing the screen frequency, the display state of the LCD (hold type display method) can be brought close to the display state of the CRT (impulse type display method), and image quality degradation due to motion blur that occurs during video display can be reduced. It becomes possible to improve.

[0015] Here, in the motion compensation frame interpolation process, detection of motion vectors is indispensable for motion compensation. As this motion vector detection method, for example, “television image motion detection method” disclosed in Japanese Patent Laid-Open No. 55-162683 and “video motion vector detection” disclosed in Japanese Patent Laid-Open No. 55-162684 are disclosed. The pattern matching method described in “Asymptotic Detection Method” or the like, or “Image Motion Detection Method” disclosed in Japanese Patent Application Laid-Open No. 60-158786 and “Movie” disclosed in Japanese Patent Application Laid-Open No. 62-206980. The iterative gradient method described in “Initial Deviation Method for Image Motion Estimation” has been proposed! Speak.

In particular, the latter motion vector detection method based on the iterative gradient method can detect a motion vector that is smaller and more accurate than the pattern matching method. In other words, the motion vector detection method based on the iterative gradient method has a predetermined predetermined size of mX n pixels including m pixels in the horizontal direction and n lines in the vertical direction, for example, for each frame of the digital television signal. By subdividing into blocks, each block is subjected to repetitive gradient calculation based on the signal gradient in the screen and the physical correspondence of the signal difference value between the corresponding screens. The amount of motion is estimated.

By the way, a moving image has a high correlation between frames and has continuity in the time axis direction. In many cases, a pixel or block moving in a certain frame moves with the same amount of movement in the subsequent frame or in the previous frame. For example, in the case of a moving image in which the ball is rolling to the right force left of the screen, the ball area moves with the same amount of movement in every frame. That is, there are many cases where motion vectors have continuity between consecutive frames.

[0018] Thus, by referring to the motion vector detection result in the previous frame, the motion vector detection in the next frame can be performed more easily or more accurately. In JP-A-62-206980, as an initial value for estimating the amount of motion, among motion vector candidates already detected in a plurality of peripheral blocks including a block corresponding to the detected block. To detect the motion vector of the detected block By selecting the optimum one as the initial displacement vector and starting the value force gradient method calculation close to the true motion vector of the detected block, the number of gradient method calculations is reduced, for example, two gradient methods A method for detecting a true motion vector by calculation has been proposed.

In addition, in the “motion vector detection circuit” disclosed in Japanese Patent Application Laid-Open No. 06-217266, each block of an image signal separated by at least one field or more than one frame in order to further improve the accuracy of motion vector detection. A method has been proposed for detecting the initial displacement of the movement. Furthermore, in the block matching method, it is conceivable to perform efficient motion margin detection by changing the search order with reference to the motion vector detection results in the previous frame. As described above, when a motion vector is detected, a real-time process of frame rate conversion, for example, can be performed by using the already detected motion vector.

By the way, in television programs and movies, subtitles, so-called telops are often included in image signals. Some of them are characters that scroll (move) horizontally or vertically on the screen. Fujine, et.al., Real-Life In-Home Viewing Conditions for FPDs and Statistical Characteristics of Broadcast Video, Digest AM— FPD '06 [Accordingly, the motion speed of subjects in general TV programs is mainly The telop scrolling speed of TV programs is 13.8 degZsec on average and 35.9 degZsec at maximum, while the frequency of telop appearance is 10 to 20 degZsec. In other words, scrolling telops often move faster and faster than typical subjects in TV programs.

Disclosure of the invention

Problems to be solved by the invention

[0021] Normally, in a moving image, the faster the movement of an object, the greater the change between frames, making it difficult to accurately estimate a motion vector. In other words, in FRC, the faster the moving object, the more difficult it is to generate an interpolated image. As described above, telops used in TV programs often move at a higher speed than ordinary subjects, so telops are difficult to accurately generate interpolated images. It can be said.

[0022] In general, when a subject photographed by a camera moves quickly, Includes blur caused by light accumulation time (camera blur). As described above, motion blur caused by the hold-type display method is less noticeable for an image originally including blur. Also, when FRC is performed, even if motion vector detection fails and the interpolated image fails, the failure is not noticeable. On the other hand, since the telop is an image that was synthesized later, it does not include camera blur even if the movement is fast. For this reason, the motion blur caused by the hold-type display method is conspicuous and the FRC functions effectively.On the other hand, if the FRC motion vector detection fails and the interpolated image of the telop part fails, the failure occurs. Is conspicuous.

[0023] In order to read the contents of the telop, the viewer looks closely at the scrolling telop and follows it. For this reason, if the FRC motion vector detection fails and the interpolated image appears in the telop part, there is a problem that the image quality deterioration is particularly noticeable for the viewer.

[0024] The present invention has been made in view of the above problems, and an image display device capable of preventing image quality deterioration of a telop portion resulting from motion compensation type frame rate conversion (FRC) processing, and An object is to provide a method, an image processing apparatus, and a method.

Means for solving the problem

[0025] The first invention of the present application interpolates an image signal subjected to motion compensation processing between frames or fields of an input image signal, thereby allowing the number of frames or fields of the input image signal to be interpolated. An image display device comprising rate conversion means for converting the signal into a display panel and detecting means for detecting a feature quantity of one or more telops included in the input image signal. Further, the motion compensation processing in the rate conversion means is controlled based on a feature amount of one or more telops.

[0026] The second invention of the present application is characterized in that the feature amount of the one or more telops is an area of one or more telops moving in a predetermined direction.

[0027] In the third invention of the present application, the detecting means divides the screen into a plurality of regions, obtains an average deviation of the average vector for each region, and sets a value obtained by multiplying this by a predetermined coefficient as a threshold value. The distance force between the average vector for each area and the average vector for the entire screen is detected as a telop area. [0028] The fourth invention of the present application is characterized in that different motion compensation processing is performed in the detected telop area and other areas.

[0029] The fifth invention of the present application is characterized in that motion compensation processing is performed only for the detected one or more telop regions, and motion compensation processing is not performed in other regions. .

[0030] According to a sixth aspect of the present invention, with respect to an area other than the detected one or more telop areas, the frame or field is inserted between frames or fields of the input image signal. An image signal is inserted.

[0031] The seventh invention of the present application is an image in which linear interpolation processing is performed between frames or fields of the input image signal for regions other than the detected one or more telop regions. It is characterized by interpolating the signal.

[0032] The eighth invention of the present application is characterized in that a filtering process is performed on a boundary portion between the one or more detected telop regions and other regions.

[0033] A ninth invention of the present application is characterized in that the feature amount of the one or more telops is a moving speed Z direction of the one or more telops moving in a predetermined direction.

[0034] In a tenth invention of the present application, the detecting means divides the screen into a plurality of regions, obtains an average deviation of the average vector for each region, and sets a value obtained by multiplying this by a predetermined coefficient as a threshold value. The distance force between the average vector for each area and the average vector for the entire screen The area larger than the threshold is detected as a telop area, and the average vector of the vector in the detected telop area is obtained. It is characterized by detecting the moving speed of the telop as the Z direction.

[0035] An eleventh aspect of the present invention is characterized in that the motion compensation processing is performed using the detected movement speed Z direction of one or more telops.

[0036] The twelfth invention of the present application is characterized in that the feature amounts of the one or more telops are one or more telop regions moving in a predetermined direction and a moving speed Z direction.

[0037] In a thirteenth invention of the present application, the detecting means divides the screen into a plurality of regions, obtains an average deviation of the average vector for each region, and sets a value obtained by multiplying this by a predetermined coefficient as a threshold value. The distance force between the average vector of each area and the average vector of the entire screen The area larger than the threshold is detected as a telop area, and the vector in the detected telop area It is characterized in that the average vector is obtained and detected as the moving speed z direction of the telop.

[0038] The fourteenth invention of the present application is characterized in that the motion compensation processing is performed on the detected one or more telop areas using the moving speed Z direction of the detected telop. It is a sign.

[0039] The fifteenth invention of the present application is characterized in that different motion compensation processing is performed in the one or more detected telop regions and the other regions.

[0040] The sixteenth invention of the present application is characterized in that motion compensation processing is performed only for the one or more detected telop regions, and motion compensation processing is not performed in other regions. To do.

[0041] In the seventeenth invention of the present application, with respect to an area other than the detected one or more telop areas, the frame or field is inserted between frames or fields of the input image signal. An image signal is inserted.

[0042] In an eighteenth invention of the present application, an image subjected to linear interpolation processing between frames or fields of the input image signal is applied to a region other than the detected one or more telop regions. It is characterized by interpolating the signal.

[0043] The nineteenth invention of the present application is an image display device characterized in that a filtering process is performed on a boundary portion between the one or more detected telop regions and other regions.

[0044] The twentieth invention of the present application converts the number of frames or the number of fields of the input image signal by interpolating the image signal subjected to the motion compensation process between frames or fields of the input image signal. An image display apparatus comprising rate conversion means for outputting to a display panel, wherein the rate conversion means converts the frame or field of the input image signal into a plurality of blocks having a predetermined size. A motion vector detecting unit that detects a motion vector representing the magnitude and direction of motion between input image signals separated by at least one frame or one field or more for each block, and the motion vector detecting unit A storage unit that accumulates at least one frame or one field of motion vectors detected for each block, and the storage unit Using the stored motion vectors, and terrorism-up information detection unit for detecting a feature amount of one or more telop included in the input image signal, the one or more telop detected by the telop information detecting unit Using the feature quantity, select the motion vector of the value most suitable for the motion of the detected block from the candidate vector group read from the motion vectors stored in the storage unit as the initial displacement vector of the detected block. Using the initial displacement vector selected by the initial displacement vector selection unit and the initial displacement vector selected by the initial displacement vector selection unit using the feature amount of the telop detected by the telop information detection unit. Thus, the motion vector of the detected block is obtained and output, and the motion vector calculation unit is stored in the storage unit.

[0045] In a twenty-first invention of the present application, the initial displacement vector selection unit performs different processing in the one or more telop regions detected by the telop information detection unit and other regions. And

[0046] In a twenty-second invention of the present application, the initial displacement vector selection unit is a candidate close to the average vector of the entire screen in a region other than the one or more telop regions detected by the telop information detection unit. A vector is preferentially selected.

[0047] In a twenty-third invention of the present application, the initial displacement vector selection unit preferentially selects a candidate vector close to a zero vector in a region other than the one or more telop regions detected by the telop information detection unit. It is characterized by selecting.

[0048] In a twenty-fourth aspect of the present invention, the initial displacement vector selection unit adds the motion vector of the one or more telops detected by the telop information detection unit to the candidate vector for processing. It is characterized by.

[0049] In a twenty-fifth aspect of the present application, the initial displacement vector selection unit detects the telop information for blocks corresponding to the one or more telop regions detected by the telop information detection unit. The motion vector of the one or more telops detected by the section is added to the candidate vector and processed.

[0050] In a twenty-sixth aspect of the present application, the initial displacement vector selection unit moves the one or more telops in the candidate vector in the one or more telop regions detected by the telop information detection unit. The initial displacement vector is selected by weighting that makes it easy to select vectors.

[0051] According to a twenty-seventh aspect of the present invention, the motion vector calculation unit includes the telop information detection unit. For a block corresponding to the detected one or more telop regions, a vector in the same direction as the direction of the motion vector of the one or more telops detected by the terror information detection unit is present. The calculation method is changed so as to be obtained.

[0052] The twenty-eighth aspect of the present invention converts the number of frames or the number of fields of the input image signal by interpolating the image signal subjected to the motion compensation process between frames or fields of the input image signal. An image display method comprising a rate conversion step, comprising a detection step for detecting a feature amount of one or more telops included in the input image signal, and the detected feature amount of the one or more telops. Based on this, the motion compensation processing in the rate conversion step is controlled.

[0053] The twenty-ninth invention of the present application converts the number of frames or the number of fields of the input image signal by interpolating the image signal subjected to the motion compensation process between frames or fields of the input image signal. An image display method comprising a rate conversion step, wherein the rate conversion step divides a frame or a field of the input image signal into a plurality of blocks having a predetermined size, and at least one for each block. A motion vector detecting step for detecting a motion vector representing the magnitude and direction of motion between the input image signals separated from the frame or one field or more, and the motion vector detecting step force includes at least a motion vector detected for each block. A storage step for storing one frame or one field, and the storage Using the motion vector, a telop information detection step for detecting one or more telop feature amounts included in the input image signal, and using the detected one or more telop feature amounts, the storing is performed. Initial displacement that selects the motion vector of the value most suitable for the motion of the detected block from the candidate vector group read out from the motion vectors accumulated in step as the initial displacement vector of the detected block Using the vector selection step and the characteristic amount of the detected telop, the motion vector of the detected block is obtained by performing a predetermined calculation using the initial displacement vector selected in the initial displacement vector selection step as a starting point. And a motion vector calculation step for obtaining and outputting.

[0054] In the thirtieth invention of the present application, the number of frames of the input image signal is interpolated by interpolating the image signal subjected to the motion compensation process between frames or fields of the input image signal. Alternatively, the image processing apparatus includes a rate conversion unit that converts the number of fields and outputs the image, and includes a detection unit that detects a feature amount of one or more telops included in the input image signal. The motion compensation processing in the rate conversion means is controlled based on a feature value of one or more telops.

[0055] The thirty-first invention of the present application converts the number of frames or the number of fields of the input image signal by interpolating the image signal subjected to the motion compensation process between frames or fields of the input image signal. Output rate converting means, and the rate converting means divides the frame or field of the input image signal into a plurality of blocks having a predetermined size, and for each block. A motion vector detection unit that detects a motion vector representing the magnitude and direction of motion between input image signals separated by at least one frame or one field or more is provided, and the motion vector detection unit force is detected for each block. A storage unit that accumulates at least one frame or one field of motion vectors, and motion stored by the storage unit A telop information detection unit that detects a feature amount of one or more telops included in the input image signal using a vector and a feature amount of one or more telops detected by the telop information unit. Initial displacement vector selection for selecting a motion vector having a value most suitable for the motion of the detected block from the candidate vector group read out from the motion vectors stored in the storage unit as the initial displacement vector of the detected block And a telop feature detected by the telop information detection unit, using the initial displacement vector selected by the initial displacement vector selection unit as a starting point and performing a predetermined calculation, It has a motion vector calculation unit that obtains and outputs a vector and accumulates it in the storage unit.

[0056] The thirty-second invention of the present application converts the number of frames or the number of fields of the input image signal by interpolating the image signal subjected to the motion compensation process between frames or fields of the input image signal. An image processing method comprising a rate conversion step, comprising a detection step for detecting a feature value of one or more telops included in the input image signal, wherein the detected feature value of the one or more telops is included. Based on this, the motion compensation processing in the rate conversion step is controlled. [0057] The thirty-third invention of the present application converts the number of frames or the number of fields of the input image signal by interpolating the image signal subjected to the motion compensation process between frames or fields of the input image signal. An image processing method comprising a rate conversion step, wherein the rate conversion step divides a frame or a field of the input image signal into a plurality of blocks having a predetermined size, and at least one for each block. A motion vector detecting step for detecting a motion vector representing the magnitude and direction of motion between the input image signals separated from the frame or one field or more, and the motion vector detecting step force includes at least a motion vector detected for each block. A storage step for storing one frame or one field, and the storage Using the motion vector, a telop information detection step for detecting one or more telop feature amounts included in the input image signal, and using the detected one or more telop feature amounts, the storing is performed. Initial displacement that selects the motion vector of the value most suitable for the motion of the detected block from the candidate vector group read out from the motion vectors accumulated in step as the initial displacement vector of the detected block Using the vector selection step and the characteristic amount of the detected telop, the motion vector of the detected block is obtained by performing a predetermined calculation using the initial displacement vector selected in the initial displacement vector selection step as a starting point. And a motion vector calculation step for obtaining and outputting.

The invention's effect

[0058] According to the present invention, with the above-described configuration, it is possible to more accurately perform motion compensation processing on a telop portion that moves in a predetermined direction on the screen. As a result, the presence of a telop exists. The image quality of the area can be improved. Brief Description of Drawings

FIG. 1 is a block diagram showing a schematic configuration of an FRC drive display circuit in a conventional liquid crystal display device.

FIG. 2 is a diagram for explaining frame rate conversion processing by the conventional FRC drive display circuit shown in FIG. 1.

FIG. 3 is a diagram for explaining interpolation frame generation processing by a motion vector detection unit and an interpolation frame generation unit. [4] FIG. 4 is a functional block diagram illustrating a configuration example of a motion vector detection unit in a frame rate conversion unit included in the image display device according to the embodiment of the present invention.

5 is a functional block diagram showing a configuration example of an initial displacement vector selection unit in FIG. [6] FIG. 6 is a functional block diagram showing another configuration example of the initial displacement vector selection unit in FIG.

[7] FIG. 7 is a functional block diagram showing still another configuration example of the initial displacement vector selection unit in FIG.

FIG. 8 is a vector diagram for explaining a method of calculating a motion vector V by two iteration gradient methods.

FIG. 9 is a schematic diagram for specifically explaining a motion vector V of an image moved between the previous frame and the current frame one frame before.

[10] FIG. 10 is an explanatory diagram showing a state in which an image is decomposed into a plurality of blocks.

FIG. 11 is an explanatory diagram showing a telop that moves in the horizontal direction on the screen.

[12] FIG. 12 is an explanatory diagram showing a state in which the screen is divided into a plurality of band-like regions.

FIG. 13 is an explanatory diagram showing a state in which the screen is divided into an area including a telop and an area other than that.

FIG. 14 is an explanatory diagram showing the relationship between the average vector of the telop area, the average vector of the area other than the telop, and the average vector of the entire screen.

FIG. 15 is an explanatory diagram showing the relationship between the average vector of the telop area, the average vector of the area other than the telop, and the average vector of the entire screen.

[16] FIG. 16 is an explanatory diagram showing an example of detecting two pieces of telop information.

圆 17] An explanatory diagram showing another example in the case of detecting two pieces of telop information.

Explanation of symbols

'Frame delay part, 2' Initial displacement vector selection part, 2a 'Coordinate transformation part, 2b, Subtraction part, 2c, Absolute value accumulation part, 2d 2e--'Telop vector addition decision unit, 3 · · · Motion vector operation unit, 4 ·' Vector memory, 5 · · Telop information detection unit, 100 · 'Frame rate conversion (FRC) unit, 101 · · · · Motion vector detection unit, 102 · · Interpolation frame generation unit, 103 · · · Electrode drive unit, 104 · · · LCD panel. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the image display device of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals are given to the same parts as those in the conventional example described above, and the description will be given. Omitted. Note that the present invention can be applied to any of a field signal, an interpolated field signal, a frame signal, and an interpolated frame signal, since both (field and frame) are in a similar relationship. The frame signal and the interpolated frame signal will be described as typical examples.

[0062] (1) Overall configuration and usage of telop information

FIG. 4 is a functional block diagram showing an example of the motion vector detection unit provided in the image display device of the present invention. The internal configuration of the motion vector detection unit 101 included in the FRC unit 100 of the image display device shown in FIG. It is for explaining in detail. The motion vector detection unit 101 of the present embodiment includes a frame delay unit 1, an initial displacement vector selection unit 2, a motion vector calculation unit 3, a vector memory 4, and a telop information detection unit 5.

[0063] The motion vector detection unit 101 according to the present embodiment uses a plurality of input image signals input for each frame, each having a predetermined size, for example, m pixels Xn lines (m and n are integers). For example, the frame delay unit 1 delays each divided block, for example, the motion indicating the direction and magnitude of the motion with the corresponding block in the input image signal one frame before The vector vector is used to determine the vector of motion vectors that have already been detected and stored in the vector memory 4, and the telop information obtained by the telop information detector 5 is used together. The initial displacement vector selection unit 2 that selects an optimal motion vector as an initial displacement vector in the detected block, and the telop information using the initial displacement vector as a starting point Used, and a motion base Tato Le computation unit 3 for obtaining the correct true motion vectors in 該被 detection block for example by gradient method calculation twice.

[0064] In particular, in the present embodiment, the telop information detection unit 5 is provided, and the telop information obtained thereby is used for processing in the initial displacement vector selection unit 2 or the motion vector calculation unit 3. There is a feature. In the initial displacement vector selection unit 2, different processing is performed in the area where the telop exists and other areas, or the moving speed of the telop is changed. Degree Select the initial displacement vector considering the Z direction, or combine both. Further, the motion vector calculation unit 3 performs vector calculation in consideration of the z moving direction z direction in the area where the telop exists. By performing such processing, a more accurate detection vector can be obtained particularly in a region where a telop exists.

[0065] In the telop information detection unit 5, as the telop feature amount (terror information) included in the input image signal, for example, telop area information indicating which motion detection block in the screen corresponds to the telop, The telop vector information indicating the moving speed Z direction of the telop is detected. If there are multiple telops on the screen, telop area information and telop vector information may be detected for each of them. Details of the telop information detection unit 5 will be described later.

[0066] Further, here, the power for explaining an example using the iterative gradient method as a calculation method in the motion vector calculation unit 3 is not limited to this iterative gradient method, and a block matching method or the like may be used.

In more detail, as described above, the motion vector detection unit 101 shown in FIG. 4 includes the initial displacement vector selection unit 2, the motion vector calculation unit 3, the vector memory 4, and the telop information detection unit. It is composed of 5 and The initial displacement vector selection unit 2 and the motion vector calculation unit 3 are supplied with the current frame signal and the previous frame signal delayed by one frame via the frame delay unit 1, respectively.

[0068] The initial displacement vector selection unit 2 calculates the medium force of the already detected motion vector obtained by the motion vector calculation of the previous frame, the value most suitable for the motion of the detected block, for example, the value closest to the motion of the detected block. This is a selection circuit that selects a motion vector as an initial displacement vector as a starting point of gradient method computation, and selects an appropriate motion vector from the above-described candidate vector group and telop vector. In the initial displacement vector selection unit 2, for example, as described above, the previous frame signal is divided into blocks of m pixels Xn lines, and the current frame signal is used as a reference for selecting the initial displacement vector for each of the divided blocks. And the previous frame signal.

[0069] As shown in FIG. 5, for example, the initial displacement vector selection unit 2 includes a coordinate conversion unit 2a, a subtraction unit 2b, an absolute value accumulation unit 2c, a selection unit 2d, and a telop vector addition determination unit 2e. is doing. In the initial displacement vector selection unit 2, motion vectors of 8 blocks around the block corresponding to the detected block sequentially read from the vector memory 4, that is, candidate vector groups and 1 output from the telop information detection unit 5 Two or more telop vectors and telop area information, a previous frame signal, and a current frame signal are input.

[0070] In the telop vector addition determination unit 2e, one or more telop vectors and telop area information are input, and when the block being processed corresponds to a telop area, the telop vector in the telop area is coordinate-transformed. Output to part 2a. When the block being processed corresponds to a plurality of telop areas, the telop vectors in each of the plurality of telop areas, that is, the plurality of telop vectors are output to the coordinate conversion unit 2a.

[0071] Each motion vector of each candidate vector group and one or more telop vector forces output from the telop vector addition determination unit 2e are candidates for the initial displacement vector. The initial displacement vector candidates are supplied to the respective coordinate conversion units 2a, and the target block of the previous frame signal supplied from the frame delay unit 1 is displaced by the motion vector to perform coordinate conversion to the current frame. The coordinate conversion result is supplied to each subtraction unit 2b.

[0072] In this embodiment, the candidate vector group is a force that uses the motion vector of the previous frame detected in eight blocks around the detected block as the candidate vector group for selecting the initial displacement vector of the detected block. Of course, these candidate vector groups are not limited to this example, and may be configured to determine the motion vector forces already detected in other regions.

[0073] Each subtraction unit 2b performs a subtraction process between the previous frame signal coordinate-converted by the coordinate conversion unit 2a and the input current frame signal, and calculates a difference for each pixel. The difference results are supplied to the absolute value accumulating unit 2c. Each absolute value accumulating unit 2c calculates the absolute value of the difference of each pixel, accumulates the absolute value difference for the number of pixels of the block, and uses the accumulated result as the evaluation value of the candidate vector. Are output respectively.

[0074] The cumulative result obtained by the above procedure is called DFD (Displaced Field Difference). The DFD is an index indicating the degree of accuracy of the calculated vector (here, the candidate vector). The smaller the DFD value, the more the coordinates of the previous frame block and the current frame change. It shows that the corresponding candidate vector with better matching with the converted block is more suitable.

[0075] Next, the selection unit 2d that has received each accumulated result (DFD) for each block compares the accumulated result (DFD) of each block, and the candidate vector that minimizes the accumulated result (DFD) is obtained. That is, a candidate vector that is most likely to be suitable is detected, the candidate vector is selected as an initial displacement vector, and is supplied to the motion vector calculation unit 3. At this time, using the telop area information from the telop information detection unit 5, if the detected block corresponds to the telop area, processing is performed so that the telop vector is selected with priority.

More specifically, for example, when the detected block corresponds to a telop area, weighting is performed so as to reduce the cumulative result (DFD) for the telop vector among the output values from the absolute value accumulating unit 2c. . For example, it is possible to use a method of reducing the cumulative result (DFD) value for a telop vector by multiplying the cumulative result for the telop vector by a coefficient w (0 <w <1).

Note that in the above embodiment, the method of using both the telop area information and the telop vector information detected by the telop information detection unit 5 in the initial displacement vector selection unit 2 has been described. However, a configuration using only one of the information may be used. For example, an example of a configuration using only telop area information will be described with reference to FIG. In this configuration, since no telop vector is input, the telop vector addition determination unit 2e in FIG. 5 is excluded. In this example, in the selection unit 2d, when the block being processed is outside the telop area, the absolute value accumulation unit 2c is weighted so as to give priority to the average vector or 0 vector of the entire screen, and the block being processed If is a telop area, no such weighting is performed. By performing such processing, relatively fast vectors are easily selected in the telop area. That is, it is easy to select a solid that corresponds to a fast-moving telop.

Further, for example, an example of a configuration using only telop vector information will be described with reference to FIG. In this configuration, no telop area information is input. For this reason, the telop vector addition determination unit 2e in FIG. 5 is also unnecessary, and telop vectors are added to the initial displacement vector candidates for all blocks. The initial displacement for the block where the telop is present. Whether or not a telop vector is the same as or close to that of the telop vector depends on the vector detection situation in the previous frame, and is not certain. Therefore, it is possible to improve the possibility of selecting a more appropriate initial displacement vector by separately providing a telop vector as a candidate.

[0079] Furthermore, it goes without saying that one or more of the above-described methods for using telop area information and telop vector information may be used in any combination.

The motion vector calculation unit 3 uses the current frame signal and the previous frame signal to detect a motion vector for each block, and uses the initial displacement supplied from the initial displacement vector selection unit 2. This is an arithmetic circuit that uses the gradient method to calculate the true motion vector from the previous frame signal to the current frame signal, starting from the vector. Note that the motion vector calculation method by the gradient method calculation is detailed in each of the above-mentioned patent documents and non-patent documents, so the description thereof is omitted here, but the initial displacement vector force is used in this embodiment. An iterative gradient method will be described below as an example.

[0081] For example, in the gradient method calculation, the motion displacement VI, in which the motion amount of the current frame is estimated from the coordinate position obtained by displacing the previous frame signal with the initial displacement vector VO (α, β), is Obtained according to equations (1) and (2).

[0082] [Equation 1] Formula (ι)

[0083] [Equation 2]

Vy = ∑ (sign (Ay)-DFD (x, ^)) / ∑ | | Equation (2)

[0084] However, in equations (1) and (2), Vx is the X direction component of the difference between the motion vectors VO and VI, and Vy is the y direction component of the difference between the motion vectors VO and VI. Here, ∑ represents that a sum is obtained by calculating all the coordinates in the block area of m pixels Xn lines, for example, 8 pixels X 8 lines. Δ χ is the gradient in the X direction of the image luminance at the target coordinate (difference value from the adjacent pixel in the X direction), and Δ y is the gradient in the y direction of the image luminance at the target coordinate (with the adjacent pixel in the y direction). Difference), DFD (x, y) is the coordinates of the previous frame (X, y) and the coordinates of the current frame (X + a, y + β) and the inter-frame difference value, which is the same calculation method as described above. Also, sign (Δχ) and sign (Ay) are signs indicating the direction of the gradient represented by either +1, —1, or 0, respectively.

[0085] For example, in the case of two iteration gradient methods, the initial displacement vector is set to VO as shown in Fig. 8.

The first displacement VI and the second displacement V2 are obtained, and a motion vector V obtained by adding them is obtained by the following equation (3).

[0086] [Equation 3]

V = VO + V1 + V2 ... Formula (3)

[0087] As shown in FIG. 9, according to the equation (3), the image power existing in the block of the coordinates (ml, nl) in the previous frame and the coordinates of the image frame in the current frame (ml + α θ , nl + j8 0), the amount of movement is calculated as vector V when moving to the block at the coordinate position. Here, FIG. 9 is a schematic diagram for specifically explaining the motion vector V of the image moved between the previous frame and the current frame one frame before.

In this way, the motion vector V obtained by the motion vector calculation unit 3 in FIG. 4 is stored in the vector memory 4 and is used for selecting an initial displacement vector used for calculating a motion vector in the next frame and thereafter. Is used as a candidate vector.

[0089] As described above, by extracting the motion characteristics of the entire screen and applying the initial displacement vector compensated based on the motion characteristics of the entire screen, erroneous detection of the initial displacement vector is prevented, for example, twice. It is possible to correctly calculate the true motion vector for each block of the current frame signal with a small number of computations by the iterative gradient method.

Here, one or more telop area information from the telop information detection unit 5 is input to the motion vector calculation unit 3, and special processing is performed when the detected block corresponds to the telop area. May be. For example, if the direction of the telop vector is the horizontal direction, the iterative gradient method may be performed using only the X value, and the final motion vector may be limited to the horizontal direction. Alternatively, when the direction of the telop vector is the vertical direction, the iterative gradient method may be performed using only the y value, and the finally obtained motion vector may be limited to the vertical direction. This is based on the direction of the telop vector. This is to make it easier to follow.

[0091] In the above description, as the motion vector calculation method in the motion vector calculation unit 3, the iterative gradient method using one or more gradient method operations is adopted. However, the present invention is not limited to this. A pattern matching method and other calculation methods may be used.

[0092] The vector memory 4 is a storage unit including a RAM (Random Access Memory) that accumulates at least one frame of motion vectors already detected for each block, and its input terminal is a motion vector calculation unit. For example, the motion vector calculation unit 3 sequentially updates the motion vector detected in the corresponding block at the address corresponding to the position of each block divided into 8 pixels x 8 lines. And is configured to accumulate.

The motion vector detection result for each block is output from the motion vector detection unit 101 by the above-described procedure.

[0094] Then, the interpolation frame generation unit 102 generates an interpolation image using the motion vector detection result for each block. At this time, the interpolation image generation using the motion vector may be performed in the entire area of the screen, the interpolation image generation using the motion vector is performed in the telop area, and the motion vector is used in the other areas. For example, the same image as the previous frame or the subsequent frame may be repeatedly output without generating the interpolated image.

That is, when no telop is detected, motion compensation processing is not performed on the entire screen, and when telop is detected, motion compensation processing is performed only on the telop region, and other regions are detected. It is okay if no motion compensation processing is performed.

As described above, a subject photographed by a normal camera includes a blur (camera blur) caused by the light accumulation time of the camera when the movement is fast. If there are many camera blurs that originally exist, even if the motion blur is reduced by FRC, the effect is difficult to understand. On the other hand, since the telop is composed of images afterwards, camera blur is not included even if the motion is fast, and the motion blur improvement effect by FRC is high. Therefore, even if motion compensation processing is performed only in the telop area, a large improvement effect can be obtained visually, and the interpolation image generation processing is limited to the telop area, so that the interpolated image can be obtained. The amount of processing to generate can be reduced.

[0097] Further, in this way, an interpolated image is generated by motion compensation for only the telop area. In some cases, the presence or absence of motion compensation processing clearly appears in the image at the boundary between the telop area and the other areas. In order to reduce this, the boundary between the telop area and the other areas is subjected to filter processing such as applying a Lonos filter to continuously change the strength of the motion compensation processing. It is desirable to suppress the conspicuousness.

Here, for regions other than the telop region that is not subjected to motion compensation interpolation processing, as described above, image signals of the same frame that are not subjected to motion compensation interpolation processing are output continuously at high speed. That is, the frame rate may be converted by inserting the image signal of the frame between the frames of the input image signal, or an image generated by linear interpolation processing from the previous and subsequent frames may be interpolated. That is, the frame rate may be converted by interpolating the image signal subjected to the linear interpolation process between the frames of the input image signal. In the linear interpolation process, an interpolation frame is obtained from the image signals of the previous and subsequent frames by linear interpolation with a frame interpolation ratio a.

[0099] (2) Example of telop information detection method

As described above, the telop information detection unit 5 detects the telop information using the already detected motion vector obtained by the motion vector calculation of the previous frame stored in the vector memory 4. An example of a specific method for realizing the telop information detection unit 5 will be described in detail below.

[0100] Information that can be used for telop detection is only the motion vector of each motion detection block stored in the vector memory 4 and the texture information of each motion detection block. Of these, the colors of the telop vary, so the texture information is auxiliary and cannot be used. For this reason, it is necessary to detect telop area information and telop vector information from the motion vector information of each motion detection block.

[0101] In addition to the telop, there are various moving objects such as people and cars in the video. The entire screen moves relative to the camera pan! /, Sometimes. For this reason, it is difficult to determine, for example, a simple determination that a fast-moving region is a telop region, that is, whether the motion vector is an absolute force telop. Therefore, in this embodiment, the telop area and the telop speed are calculated using statistical information such as the difference between the average vector of the entire screen and the motion vector of each motion detection block, and the average deviation of the motion vectors. To detect.

[0103] Fig. 10 shows a state in which an image is decomposed into blocks for vector detection. The overall size of the image is Wa pixels wide and Ha pixels high. When this image is divided into motion detection blocks with a width of Wb pixels and a height of Hb pixels, the number of blocks is m horizontal blocks and n vertical blocks. Normally, the total number of pixels in an image is divisible by an integer number of blocks. That is, Wa = WbXm and Ha = HbXn.

[0104] For example, in a high-definition resolution image (Wa = 1920 pixels, Ha = 1080 pixels) and the block size is 8X8 pixels, m = 240 and n = 135. Each motion detection block is called B (i, j), and the motion vector detected by each motion detection block is (V−x (i, j), V_y (i, j)).

Here, since many telops move in the horizontal direction, in this embodiment, telops that move in the horizontal direction are set as detection targets. As shown in Fig. 11, the telop that moves in the horizontal direction is located in a horizontally long belt-like area on the screen. Therefore, as shown in FIG. 12, the screen is divided into n horizontally long strip-shaped regions L (1) to L (n), and it is determined whether or not each region includes a telop.

[0106] The belt-like region L (j) includes the motion detection block B (l, j) force in FIG. 10 as well as B (m, j). If the average vector of motion vectors of motion detection blocks included in L (j) is (Vave—x (j), Vave_y (j)),

[0107] [Equation 4]

Vave _ x (j) x (i, j) ... Equation (4)

[Equation 5] νανβ_γα) =… Equation (5)

[0109]. [0110] If the average vector (overall average vector) of motion vectors of all motion detection blocks is (V ave-X, Vave-y),

[0111] Garden

Vave: c = 丄 y ove () = J- Y x (i, j)… Equation ( ⁶ )

n mn _{f = 1 i = 1}

[0112] [Equation 7]

Vave_y =-† ^ Vave _ y (j) = —∑∑V _ y (i, j)… Equation ( ⁷ )

ft j- ΪΪΙΥΙ f ~ if ₌ \

[0113]

[0114] Now, as shown in FIG. 13, the screen is divided into an area including a telop and an area other than that. The height of the telop area when the screen height is 1 is k. However, it is assumed that the telop area does not exceed half of the screen. That is,

[0115] [Equation 8]

0≤k <0. 5 Equation (8)

Assume that [0116]. The area other than the telop is 1-k. In addition, when the area other than the telop is divided into two or more by the telop area, each height is added.

[0117] Next, the average of the motion vectors of the motion detection blocks included in the telop area is (Vt-x, V t_y), and the motion detection block included in the area other than the telop (referred to as the background area in the present specification) If the average motion vector is (Vb—x, Vb—y), the average vector of the telop area, the average vector of the area other than the telop, and the average vector of the entire screen are

[0118] [Equation 9]

Vave_ x = kVt x + (1 -k) Vb x… Equation (9)

[0119] [Equation 10] Vave_y = kVt_y + (1 -k) Vb_y… Equation (io)

[0120] The relationship is established.

[0121] Actually, not all blocks in the telop area have the same movement level as the movement speed of the telop. For example, a block where a telop character is interrupted has a motion vector other than the moving speed of the telop. However, in the present embodiment, for the time being, it is assumed that all the blocks in the telop area have the moving speed of the telop, and the following explanation proceeds. This assumption will be described later.

[0122] In the present embodiment, since the telop moving in the horizontal direction is set as the detection target, the following description will be made focusing on the horizontal value of each average vector, that is, the X value of the vector.

[0123] The relationship between the average vector Vt—x of the telop area, the average vector Vb— x of the area other than the telop, and the overall average vector Vave—x in Equation (9) is shown in FIG. 14 and FIG. become.

FIG. 14 illustrates the case of Vb—X and Vt—X. Vave—x is located between Vb—x and Vt—x, and the ratio between the distance between Vb—X and Vave—X and the distance between Vave—x and Vt—x is k: 1—k. This relationship holds regardless of the magnitude or sign of Vave—x, Vb—x, and Vt—x. From the condition of equation (8),

[0125] [Equation 11] k <1— k ... Formula (1 1)

[0126] always holds. Thus, the distance between Vb—X and Vave—X is always less than the distance between Vave—x and Vt—x.

FIG. 15 shows the case of Vt—X and Vb—X. Vave—x is located between Vt—x and Vb—x, and the ratio between the distance between Vt—X and Vave—X and the distance between Vave—x and Vb—x is 1 k: k 〖 This relationship holds regardless of the magnitude or sign of Vave—x, Vt—x, and Vb—x. Also, equation (11) always holds from the condition of equation (8). Thus, as in Figure 14, the distance between Vt X and Vave x is always between Vave x and Vb x. Less than distance.

[0128] That is, even if Vb— X <Vt— x and Vt— x <Vb— x, Vb— x and Vave

The distance between —x is always less than the distance between Vave—X and Vt—x. That means

[0129] [Equation 12]

I Vb― X— Vave― x | <| Vt—x— Vave― x |… Formula (1 2)

[0130] always holds.

[0131] Therefore, a threshold T is prepared,

[0132] [Equation 13]

I Vb― X― Vave― x | <T <| Vt― x― Vave― x |… (1 3)

[0133] It is determined to be Using this threshold T, the distance between Vave_x (j) and Vave— x and the threshold for the average vector X value Vave— x (j) of the motion detection block included in each band Lj in FIG. Compared with T, if it is larger than Τ, it can be determined that the band-like region Lj is likely to belong to the telop region. That is, for a certain band region Lj,

[0134] [Equation 14]

T <I Vave—x (j) —Vave—x | (1 4) [0135] When the following expression is established, the band-like area is determined as a telop area.

[0136] The problem here is how to set the threshold T. The method is described below.

[0137] The setting condition of the threshold T is as shown in the equation (13). From this equation (13), it can be seen that in order to determine the threshold T, information on I Vb— X— Vave— X | and | Vt—x— Vave— x | Vb—x cannot be obtained directly. This is because the power of which region is a telop region is not known in advance.

[0138] where I Vb—x— Vave— X | and | Vt—x— Vave— x | is the difference between the global average vector and the average vector of the background area, and the global average vector and the telop area, respectively. flat This is the difference between the average vectors, and its value is closely related to the degree of motion vector variation. Therefore

The threshold value T is determined by using the average deviation, which is one of the measures of data dispersion.

[0139] The average vector Vave of each strip region Lj— If the average deviation of x (j) is M, M is

[0140] [Equation 15]… Formula (1 5)

[0141] Multiply the average deviation M by a constant α

[0142] [Equation 16]

Τ = ひ Μ… Formula (1 6)

[0143] Find the appropriate constant a as follows.

[0144] First, consider the case of Vb—X and Vt—X. At this time, if the average deviation M is expressed using Vt—x and Vb_x,

[0145] [Equation 17] = (Vt_x- Vave_x) k + (Vave_x- Vb_x) (1— k)… Equation (l 7)

[0146] Substituting equation (9) into equation (17) and rearranging,

[0147] [Equation 18]

M = 2k (1-k) (Vt__x-Vb_x)… Equation (i s)

[0148] is obtained.

[0149] From Equation (13) and Equation (16),

[0150] [Equation 19]

| Vb—X—Vave one X | <Qr <| Vt— x— Vave— x |… Equation (1 9) [0151].

[0152] On the other hand, from the condition of Vb— x <Vt x and Equation (9), [0153] [Equation 20]

| Vb_x-Vave_x | = | k (Vt_x-Vb_x) | = k (Vt_x— Vb— x)… Formula (2 0)

[0154] [Equation 21] ... Formula (2 1)

[0155] is obtained.

[0156] Substituting equation (18), equation (20), and equation (21) into equation (19),

[0157] [Equation 22]

<a <—… Formula (2 2)

2 (1-k) 2k

The conditional expression “0158” is obtained.

[0159] Although detailed description is omitted, Expression (22) is obtained as a conditional expression even in the case of Vt—x <Vb—X.

[0160] The value of the constant a can be determined by assuming the height k of the telop area according to equation (22). If k = 0.2, substitute into equation (22),

[0161] [Equation 23]

0. 625 2 2.5 ... Formula (2 3)

The condition [0162] is obtained. If the constant α is set within this range, it is possible to detect a telop area of about k = 0.

[0163] Also, if k = 0.4, it is similarly substituted into equation (22),

[0164] [Equation 24]

0. 833 <<1.25… Formula (2 4)

The condition [0165] is obtained. In other words, if we try to deal with the case where there is a wider telop area, we can see that the settable range of constant a becomes narrower.

[0166] As described above, by assuming the value of the height k of the telop area, the settable range of the constant a Can guide you. Analyze the actual video to determine the tendency of the height k of the telop area, determine k, and determine the constant α according to the settable range of the constant α obtained by that.

[0167] If the constant α is determined and the average deviation Μ is obtained from the equation (15), the value of the threshold Τ can be determined from the equation (16). Here, it should be noted that the average deviation Μ also calculates the detected motion vector force. That is, the value of the threshold value 変わる changes every frame depending on the state of the detected motion vector, that is, the motion of the object in the video.

[0168] Once the value of threshold value Τ is obtained, a determination process is performed on the X value Vav e_x (j) of the average vector of each strip region Lj according to Equation (14), and whether or not the strip region is a telop region Can be determined.

[0169] Further, when each band-like area Lj is determined and it is determined which band-like area is the telop area, the average (Vt_x, Vt_y) of the motion vectors of the motion detection blocks included in the telop area is determined. Can be calculated. This is the telop vector.

[0170] Here, in the above description, it can be considered that all the blocks in the telop area are assumed to have the telop speed. Actually, not all blocks in the telop area have the same motion vector as the telop speed. The more blocks that do not contain telop characters in the telop area, for example, when telop characters are sparse, the average vector Vt—x in the telop area is larger than the true telop vector. — A value close to X. At the same time, the average vector Vb—x in the area other than the telop is close to the overall average vector Vave—X. That is, both I Vt—x—Vave—X | and I Vb—x—Vave—X |

[0171] Based on this fact, the telop area is detected if the threshold value whose setting range is limited by Equation (13) or Equation (19) is also set small, that is, if the value of O is not set small. I can't do that. However, if the threshold value T is reduced, the possibility that a non-telop area will be erroneously detected increases.

[0172] On the other hand, if the telop area does not contain telop characters and there are few blocks, for example, if telop characters are densely present, the operation can be expected almost as described above. [0173] As described above, in actual application, it is necessary to determine the constant α in consideration of the extent to which sparse telop characters are to be detected and the extent to which false detection is allowed. is there.

[0174] In the above embodiment, the telop is detected on the assumption that the telop moves in the horizontal direction. However, the case where the telop moves in the vertical direction or in the oblique direction can also be detected by the same method. In that case, the method of dividing the band-like region may be set according to the direction to be detected. For example, to detect a telop that moves in the vertical direction, the band-like area may be set as a vertically long area.

Next, a telop information detection method when there are a plurality of telops on the screen will be described. For example, as shown in FIG. 16, the screen is divided into two telop detection areas 1 and 2 at the top and bottom, and the telop area information Α and the telop vector information Va are obtained by executing the above-described telop detection method in each area. , Telop area information B and telop vector information Vb can be detected.

Alternatively, for example, as shown in FIG. 17, horizontal telop detection processing and vertical telop detection processing are executed in parallel to obtain horizontal telop area information C and telop vector information Vc. Two pieces of telop information including the telop area information D in the vertical direction and the telop vector information Vd may be detected. Here, telop area C and telop area

The common area with D corresponds to the case where the block being processed corresponds to a plurality of telop areas in the above description of the vector detection means.

[0177] According to the present embodiment, one or more pieces of telop information can be detected by the procedure as described above. The processing using the detected telop information has already been described above.

[0178] Note that the above-described telop information detection means is merely an example, and even if the telop information is detected using other means, the motion vector detection method and the interpolated image generation method according to the present invention are used. Needless to say, the present invention can be applied.

Here, it should be noted that the motion vector of each motion detection block stored in the vector memory 4 is used as an input to the telop information detection unit 5. The motion vector of each motion detection block stored in the vector memory 4 is the motion vector detection result of the previous frame. In other words, the processing of the telop information detection unit 5 is the motion beta of the previous frame. This is done using the detection results. Since telops usually exist at the same position across multiple frames, using the motion vector detection result of the previous frame as described above is not a big problem.

As described above in detail, in the motion vector detection method according to the present embodiment, a telop region and a telop vector are detected as telop feature quantities, and the result is used for initial displacement vector selection and motion vector calculation. By controlling the motion compensation processing by reflecting it, it becomes possible to perform motion vector detection in the terror region more correctly, and as a result, it is possible to improve the image quality in the telop region.

[0181] By the way, in the input image signal, the correlation between successive frames may be interrupted due to a scene change or the like. In this case, referring to the motion vector detection result of the previous frame stored in the vector memory 4 may cause a vector erroneous detection. For this reason, a method of resetting the motion vector detection result in a previous frame when the correlation between consecutive frames is interrupted due to a scene change or the like has been proposed (for example, Japanese Patent Laid-Open No. 2000-333134). Publication).

[0182] However, in the case of an input image signal in which a scrolling telop is superimposed on an image in which a scene change exists, when the reset process as described above is performed, the motion vector in the area where the telop exists is also reset, An interpolated image that scrolls with a smooth force cannot be obtained. Therefore, for the area detected as a telop area, even if a scene change occurs in the input image signal, a motion compensation process different from that for other areas is performed to obtain an interpolated image in which the telop scrolls smoothly. It is desirable to be able to

[0183] More specifically, even if a scene change occurs, the vector detection processing is continued without performing the reset processing of the motion vector detection result as described above for the telop area. Thus, even when a scene change occurs, it is possible to obtain an interpolated image in which the telop scrolls with a smooth force, and for the areas other than the telop area, the above reset process is performed when a scene change occurs. This makes it possible to prevent erroneous detection of vectors, and to achieve both image quality in the telop area and other areas. [0184] The image display device of the present invention can be applied to all image display devices having hold-type display characteristics such as an organic EL display and an electrophoretic display as well as a liquid crystal display using a liquid crystal panel as a display panel. Is possible. Needless to say, the input image signal is not limited to a television broadcast signal, but may be an image signal reproduced by an external media card!

Further, in the above description, the power described with respect to the exemplary embodiment of the image processing apparatus and method of the present invention. From these descriptions, an image processing program for executing the image processing method as a program by a computer, Also, a program recording medium in which the image processing program is recorded on a computer-readable recording medium can be easily understood.

Furthermore, in the above-described embodiment, the form in which the image processing apparatus of the present invention is integrally provided in the image display apparatus has been described. However, the image processing apparatus of the present invention is not limited to this, for example, playback of various recording media Needless to say, it may be provided in a video output device such as a device.

Claims

The scope of the claims

[1] By interpolating motion-compensated image signals between frames or fields of the input image signal, the number of frames or fields of the input image signal is converted and output to the display panel. An image display device including rate conversion means for detecting, comprising: detection means for detecting a feature amount of one or more telops included in the input image signal,

An image display device that controls the motion compensation processing in the rate conversion means based on the detected feature quantity of one or more telops.

[2] In the image display device according to claim 1,!

The image display device characterized in that the feature quantity of the one or more telops is an area of one or more telops moving in a predetermined direction.

[3] In the image display device according to claim 2,

The detection means divides the screen into a plurality of areas, obtains an average deviation of the average vector for each area, and sets a value obtained by multiplying the average vector by a predetermined coefficient as a threshold, and the average vector for each area and the entire screen An image display device that detects, as a telop region, a region in which a distance from the average vector is greater than the threshold value.

[4] In the image display device according to claim 2 or 3,

An image display device, wherein different motion compensation processing is performed in the detected telop area and other areas.

[5] In the image display device according to claim 2 or 3,

An image display device, wherein motion compensation processing is performed only on the one or more detected telop regions.

[6] In the image display device according to claim 5,

An image display device, wherein an image signal of the frame or field is inserted between frames or fields of the input image signal for an area other than the detected one or more telop areas .

[7] In the image display device according to claim 5,

For an area other than the one or more detected telop areas, the input image An image display device, wherein an image signal subjected to linear interpolation processing is inserted between frames of a signal or between fields.

[8] In the image display device according to claim 6 or 7,

An image display device, wherein a filtering process is performed on a boundary portion between the detected one or more telop regions and other regions.

[9] In the image display device according to claim 1,!

The image display device characterized in that the feature amount of the one or more telops is a moving speed Z direction of one or more telops moving in a predetermined direction.

[10] In the image display device according to claim 9,

The detection means divides the screen into a plurality of areas, obtains an average deviation of the average vector for each area, and sets a value obtained by multiplying the average vector by a predetermined coefficient as a threshold, and the average vector for each area and the entire screen A region where the distance to the average vector is greater than the threshold is detected as a telop region,

An image display device characterized in that an average vector of vectors in the detected telop area is obtained and detected as a telocity moving direction Z direction.

[11] In the image display device according to claim 9 or 10,

An image display device that performs the motion compensation processing using the movement speed Z direction of the detected one or more telops.

[12] In the image display device according to claim 1,!

The image display device characterized in that the feature amount of the one or more telops is an area of one or more telops moving in a predetermined direction and a moving speed Z direction.

[13] In the image display device according to claim 12,

[14] In the image display device according to claim 12 or 13,

The image display apparatus characterized in that the motion compensation processing is performed on the detected one or more telop areas using the moving speed Z direction of the detected telop.

[15] In the image display device according to any one of claims 12 to 14, the image display device!

An image display device, wherein different motion compensation processing is performed in the one or more detected telop regions and other regions.

[16] In the image display device according to any one of claims 12 to 14, the image display device!

[17] In the image display device according to claim 16,

[18] In the image display device according to claim 16,

For an area other than the detected one or more telop areas, an image signal subjected to linear interpolation processing is interpolated between frames of the input image signal or between fields. Image display device.

[19] In the image display device according to any one of claims 16 to 18,

[20] By interpolating motion-compensated image signals between frames or fields of the input image signal, the number of frames or fields of the input image signal is converted and output to the display panel. The rate conversion means divides a frame or a field of the input image signal into a plurality of blocks having a predetermined size, and at least for each block. A motion vector detection unit that detects a motion vector that represents the magnitude and direction of motion between input image signals separated by one frame or more than one field,

The motion vector detection unit receives at least one motion vector detected for each block. A storage unit that accumulates frames or one field,

Included in the input image signal using the motion vector stored in the storage unit

A telop information detection unit that detects a feature amount of one or more telops;

Using the feature quantity of one or more telops detected by the telop information detection unit, the motion vector of the detected block is most frequently selected from among the candidate vector group read from the motion vectors accumulated by the storage unit. An initial displacement vector selection unit that selects a motion vector having an appropriate value as an initial displacement vector of the detected block;

Using the feature amount of the telop detected by the telop information detection unit, a predetermined calculation is performed using the initial displacement vector selected by the initial displacement vector selection unit as a starting point, thereby obtaining the motion vector of the detected block. And a motion vector calculation unit that accumulates in the storage unit.

[21] In the image display device according to claim 20,

The image display device, wherein the initial displacement vector selection unit performs different processing in the one or more telop regions detected by the telop information detection unit and other regions.

[22] In the image display device according to claim 21,

The initial displacement vector selection unit preferentially selects a candidate vector close to an average vector of all screens in an area other than the one or more telop areas detected by the telop information detection unit. Display device.

[23] In the image display device according to claim 21,

The image display apparatus according to claim 1, wherein the initial displacement vector selection unit preferentially selects a candidate vector close to a zero vector in a region other than the one or more telop regions detected by the telop information detection unit.

[24] In the image display device according to claim 20,

The image display apparatus, wherein the initial displacement vector selection unit processes the motion vectors of the one or more telops detected by the telop information detection unit in addition to the candidate vectors.

[25] In the image display device according to claim 24, The initial displacement vector selection unit, for blocks corresponding to the one or more telop areas detected by the telop information detection unit, the one or more telops detected by the telop information detection unit. An image display device characterized in that the motion vector is added to the candidate vector for processing.

[26] In the image display device according to claim 24 or 25,

The initial displacement vector selection unit performs weighting so that a motion vector of the one or more telops in the candidate vector is easily selected in the region of the one or more telops detected by the telop information detection unit. An image display device that performs an initial displacement vector selection process.

[27] The image display device according to claim 20, wherein

The motion vector calculation unit, for blocks corresponding to the one or more telop areas detected by the telop information detection unit, of the one or more telops detected by the telop information detection unit. An image display apparatus characterized by changing a calculation method so that a vector in the same direction as a direction of a motion vector is obtained.

[28] The method includes a rate conversion step of converting the number of frames or fields of the input image signal by interpolating an image signal subjected to motion compensation processing between frames or fields of the input image signal. An image display method,

A detection step for detecting a feature amount of one or more telops included in the input image signal;

An image display method characterized by controlling the motion compensation processing in the rate conversion step based on the detected feature quantity of one or more telops.

[29] A rate conversion step of converting the number of frames or the number of fields of the input image signal by interpolating an image signal subjected to motion compensation between frames or fields of the input image signal is provided. An image display method,

In the rate conversion step, the input image signal is a frame of the input image signal or is divided into a plurality of blocks having a predetermined size, and an input image signal separated by at least one frame or one field or more for each block. A motion vector detecting step for detecting a motion vector representing the magnitude and direction of motion between The motion vector detecting step stores a motion vector detected for each block for at least one frame or one field;

A telop information detection step of detecting a feature quantity of one or more taps included in the input image signal using the accumulated motion vector;

Using the detected feature quantity of one or more telops, the motion vector accumulated in the storing step is selected from among the read candidate vector group, and the motion with the value most suitable for the motion of the detected block is detected. An initial displacement vector selection step of selecting a vector as an initial displacement vector of the detected block;

Using the detected feature value of the telop, a predetermined calculation is performed with the initial displacement vector selected in the initial displacement vector selection step as a starting point, thereby obtaining and outputting a motion vector of the detected block. And a motion vector calculation step.

[30] Rate conversion means for converting and outputting the number of frames or fields of the input image signal by interpolating an image signal subjected to motion compensation processing between frames or fields of the input image signal An image processing apparatus comprising:

Detection means for detecting a feature quantity of one or more telops included in the input image signal;

An image processing apparatus that controls the motion compensation processing in the rate conversion means based on the detected feature quantity of one or more telops.

[31] Rate conversion means for converting and outputting the number of frames or fields of the input image signal by interpolating an image signal subjected to motion compensation between frames or fields of the input image signal An image processing apparatus comprising:

The rate conversion means divides a frame or field of the input image signal into a plurality of blocks having a predetermined size, and each input block between input image signals separated by at least one frame or one field or more. A motion vector detection unit for detecting a motion vector representing the magnitude and direction of motion in

The motion vector detecting unit stores a motion vector detected for each block for at least one frame or one field; Included in the input image signal using the motion vector stored in the storage unit

Using the feature amount of the telop detected by the telop information detection unit, a predetermined calculation is performed using the initial displacement vector selected by the initial displacement vector selection unit as a starting point, thereby obtaining the motion vector of the detected block. And a motion vector calculation unit that stores the output in the storage unit.

[32] A rate conversion step for converting the number of frames or the number of fields of the input image signal by interpolating an image signal subjected to motion compensation between frames or fields of the input image signal. An image processing method comprising:

An image processing method comprising: controlling the motion compensation process in the rate conversion step based on the detected feature quantity of one or more telops.

[33] The method includes a rate conversion step of converting the number of frames or the number of fields of the input image signal by interpolating an image signal subjected to motion compensation processing between frames or fields of the input image signal. An image processing method comprising:

In the rate conversion step, the input image signal is a frame of the input image signal or is divided into a plurality of blocks having a predetermined size, and an input image signal separated by at least one frame or one field or more for each block. A motion vector detecting step for detecting a motion vector representing the magnitude and direction of motion between

The motion vector detecting step stores a motion vector detected for each block for at least one frame or one field;

A telop information detection step of detecting a feature quantity of one or more taps included in the input image signal using the accumulated motion vector; Using the detected feature quantity of one or more telops, the motion vector accumulated in the storing step is selected from among the read candidate vector group, and the motion with the value most suitable for the motion of the detected block is detected. An initial displacement vector selection step of selecting a vector as an initial displacement vector of the detected block;